| 摘要 |
PURPOSE:To enable power supply to be automatically stopped even if a passenger leaves a vehicle without switching OFF an electronic device mounted in a vehicle, by detecting sounds and vibrations in the vehicle and automatically stopping the power supply to the electronic device according to the detection signal. CONSTITUTION:Sounds or vibrations in a vehicle are detected by a detector 1 such as a microphone or a vibration pick-up. The detection sgnal is sent to a decision device 2 where the signal level is decided. When a signal is larger than a given level, electric power from a battery 3 is supplied for a given period of time via a relay 4 to an electronic device 5 such as a radio mechanism or the like mounted in the vehicle. On the other hand, if no new detection signal is supplied from the detector 1 during this operation the power supply to the electronic device 5 is stopped by the decision device 2. In such a manner, the system is enabled to detect only the signals that are caused by movement of the vehicle or by a passenger, and to automatically stop the power supply even if the passenger leaves the vehicle without switching OFF the electronic device 5. Thus, the battery 3 can be prevented from excessive discharge. |
